Leap year aside, February made up for its short length by serving up daily volatility swings the likes of which the stock market hasn’t seen in years. As the credit markets worked through a broadening wave of problems, equity market pros continued to delever and reprice risk in classic style — frantically. The Wall adds one worry to secure its place in the zone of fear. Bargains are popping up, but you had best know your companies and prepare to buy into intense market downdrafts in the face of mind-bending rumors of financial calamity. And it’s only March.